Laplace Law Controls Pregnancy Intervals, Circadian Timers, and Mode of
Delivery Through Exponential Uterine Wall Tension and Hormonal Milieu: A
Hypothesis 3
Abstract
Background Our hypothesis suggests another view regarding the
following: Labor physiology. Labor progress. Labor dystocia.
Objective To support the hypothesis. Study Design This
study investigated the current evidence-based literature and research
that may support the hypothesis. Results Intrinsic myometrial
cell character ensures that parturition is an autonomic, intrinsic, and
interactive repetitive contraction and relaxation cycle, secondary to
myometrial tension changes that cause labor progression and protect the
foetus against hypoxia. The progress during the first stage of labor and
what is called cervical dilatation is the complete transformation of the
cervix into the LUS, which has a clinical and radiological presentation.
The clinical presentation is effacement, and dilatation. Radiologically,
the cervix transforms into the LUS through an inverted inside-out TYVU
and an inverted U pattern formation. In the second stage of labor, the
cervix has completely transformed into the LUS which is a wedge-shaped
birth canal that extends from the vaginal vault (cervicovaginal
junction) into the physiologic retraction ring. All these changes
reverse instantly after foetal delivery, and the cervix returns to its
anatomical site and regains its full anatomical shape. Concomitant
malfunctions of the inhibitory and stimulatory systems cause labor
dystocia. Conclusion Labor dystocia is the failure of the
complete transformation of the cervix into the lower uterine segment
secondary to combined inhibitory and stimulatory system malfunction.
Most of the cervical transformation into the LUS takes place during the
third trimester and is completed during the first stage of labor. So,
the treatment of labor dystocia should focus on the causes of the
stimulatory system’s malfunction before the onset of labor. There is
evidence to support the hypothesis, and it should be in the interest of
obstetricians, physiologists, midwives, neonatologists, and those with a
research interest in maternal and family welfare.